An instant messaging service provides the end users a means for fast, interactive, mainly text-based communication. It includes both the Internet or SMS-style messaging with short, textual messages and also related value added services, such as presence management and chat room-type scenarios.
In general, presence can be considered containing various dynamic information of a user accessing the service via different means. Examples of this information are the reachability and availability of the user for communication and other, more emotional status such as mood and willingness for communication.
The retrieval and authorization of presence information has been solved in the Internet-based instant messaging solution in a proprietary way, tied usually to the whole service scenario, but not as a stand-alone service with complete two-way acquisition and authorization. No presence solution with stand-alone service model having complete two-way acquisition and authorization exist.
There is moreover a need to define a protocol using an open architecture so that various vendors can begin to offer such services.